Microstructure and mechanical properties of microalloyed steel forgings manufactured from cross-wedge-rolled preforms

Silva, M.L.N. da; Regone, Wiliam; Button, Sérgio Tonini

doi:10.1016/j.scriptamat.2005.09.023

Cited by 18 publications

(12 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In the arm region ( Figures 5D and 5B), the microstructure also consists of ferrite and pearlite grains, but the amount of acicular ferrite apparently decreases, perhaps because the reduction of heat transfer rate and the strain increasing in this region (Silva et al, 2006). However, the ausforged products which presented acicular ferrite in the microstructure showed the highest mechanical properties (UTS and YS) among the forged products.…”

Section: A B C Dmentioning

confidence: 95%

Mechanical properties of ausforged 27MnSiVS6 microalloyed steel

Caminaga

Button

2013

Rem: Rev. Esc. Minas

View full text Add to dashboard Cite

ResumoOs processos de forjamento a quente aplicados aos aços microligados, também conhecidos como aços de alta resistência e baixa liga (ARBL), têm uma extensa aplicação na produção de componentes automotivos. O objetivo desse trabalho foi o de estudar o comportamento microestrutural por microscopia óptica e o comportamento mecânico, em termos de propriedades de resistência e tenacidade do aço microligado 27MnSiVS6, quando empregado no processo denominado "ausforging", a fim de se analisarem o desempenho do processo e a qualidade dos produtos, comparando-os com os processos de forjamento a quente e a morno. Os produtos forjados provenientes do "ausforging" que foram submetidos aos ensaios de tração unidirecional, fadiga em flexão rotativa e tenacidade à fratura, apresentaram as melhores propriedades mecânicas. Os testes estatísticos aplicados aos resultados permitiram concluir que os produtos obtidos por "ausforging" apresentaram a melhor combinação de resistência mecânica e qualidade superficial dos produtos forjados, sem aumentar a carga de forjamento.Palavras-chave: "Ausforging", forjamento, metalurgia física. Abstract

show abstract

Section: A B C Dmentioning

confidence: 95%

Mechanical properties of ausforged 27MnSiVS6 microalloyed steel

Caminaga

Button

2013

Rem: Rev. Esc. Minas

View full text Add to dashboard Cite

show abstract

“…Moreover, deformation in the nonrecrystallization region increases ferrite nucleation sites through pancaking of austenite grains and creation of deformation bands. In this way, a fine microstructure will be produced after transformation [4,5].…”

Section: Introductionmentioning

confidence: 99%

A simple constitutive model for predicting flow stress of medium carbon microalloyed steel during hot deformation

2015

View full text Add to dashboard Cite

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. 1 A Simple Constitutive Model for Predicting Flow Stress of Medium Carbon Microalloyed Steel during Hot Deformation AbstractThe constitutive behavior of a medium carbon microalloyed steel during hot working over a wide range of temperatures and strain rates was studied using the Johnson-Cook (JC) model, the Hollomon equation, and their modifications. The original JC model was not able to predict the softening part of the flow curves and the subsequent modifications of the JC model to account for the softening stage and the strain dependency of constants were not satisfactory owing to the uncoupled nature of the JC approach regarding strain rate and temperature. The coupled effect of these variables was considered in the form of Zener-Hollomon parameter (Z) and the constants of the Hollomon equation were related to Z. This modification was found to be useful for the hardening stage but the overall consistency between the experimental flow curves and the calculated ones was not good. Therefore, a simple constitutive model was proposed in the current work, in which by utilization of the peak stress and strain into the Hollomon equation, good prediction abilities were attained. Conclusively, the proposed model can be considered as an efficient one for modeling and prediction of hot deformation flow curves.

show abstract

“…For the energy savings reasons attempts are made to utilize heat attained in the metal after deformation, utilizing direct cooling from deformation-end temperature as a cost-effective alternative to traditional water or oil quenching and subsequent tempering, which sometimes can also be replaced. The required combination of static tensile strength and impact strength properties, superior to those typically provided for these steels after QT treatment, are to be obtained here with TMP employing controlled cooling directly after forging, taking advantage of synergic combination of several strengthening mechanisms, such as austenite grain refinement, austenite transformation and producing fine precipitates, mostly carbides and carbonitrides, on subsequent cooling to control its products fractions and morphology [5,6,7,8]. Assumed energy savings are associated with eradication reheating prior to normalization and quenching as well as the use of blast air instead of cooling media and facilities associated which call for costly installations [9].…”

Section: Introductionmentioning

confidence: 99%

“…While TMP calls for a higher culture of managing the process, conventional forging processes are featured by scatter of forging temperature and serious gradients of temperature and strain in the bulk. In result, within-part and piece-to-piece inconsistency and repeatability problems occur, both in press and hammer forging [7,11].…”

Section: Introductionmentioning

confidence: 99%

Design of Controlled Processing Conditions for Drop Forgings Made of Microalloy Steel Grades for Mining Industry

Skubisz¹,

Żak²,

Burdek³

et al. 2015

Archives of Metallurgy and Materials

View full text Add to dashboard Cite

Effect of plastic processing and controlled cooling on microstructure and mechanical properties of experimental steel grades with microalloyed with Ti, V and/or Nb, varying in the content of Mo is presented as an offer for mining industry for replacement traditionally heat-treatable hardenability grades. The goal of the work is producing microstructure condition, which after controlled hot forging and direct heat treatment, involving quenching and self-tempering, are meant to provide good combination of mechanical properties, such as TYS 800 MPa, UTS 1050 MPa, elongation to fracture at least A5 15% and/or impact strength at room temperature KCV 60 J/cm 2 . Hardenability assessment and dilatometric examination allowed formulation of direct heat treatment guidelines, taking into consideration fields of temperature and strain in a typical hot forging process, estimated numerically, with the use of plastometric tests results, as well as the use of unique cooling cycles after forging.On the basis of numerical analysis of thermomechanical parameters and temperature progression, hot forging and direct cooling conditions were selected to achieve assumed structural components, morphology and dispersion of both grain and precipitates. For established heat transfer model and experimentally plotted cooling curves numerical analysis of direct cooling, enabled by definition of characteristic points of austenite transformation and CCT diagrams was conducted. The modeling aided with dilatometric characterization enabled prediction of transformation products distribution. The formulated conclusions were verified in the experimental sampling of forging, evaluating the applicability of designed combinations of chemical composition and cooling cycle for selected forged part for mining industry.Keywords: microalloyed steel, thermomechanical processing, direct cooling, hammer forging, grain control Przedstawiono badania wpływu warunków odkształcania na gorąco i kontrolowanego chłodzenia na efektywność umocnienia eksperymentalnych stali z mikrododatkami Nb, Ti oraz V o zmiennej zawartości Mo. Pierwszym etapem pracy było zaprojektowanie składów chemicznych stali mikrostopowych, które po kontrolowanym kuciu na gorąco oraz obróbce cieplnej, polegającej na zahartowaniu i samoodpuszczeniu odkuwki bezpośrednio po kuciu, pozwolą na uzyskanie właściwości mechanicznych, tj.: granicy plastyczności 800 MPa, wytrzymałości na rozciąganie 1050 MPa, wydłużeniu A 5 15% i udarności w temperaturze otoczenia KCV 60 J/cm 2 . W oparciu o wyniki badań hartowności i analizę dylatometryczną opracowano wytyczne bezpośredniej obróbki cieplnej, uwzględniając obliczenia równowagi faz i wpływ temperatury na udział wydzieleń w wybranych wytopach oraz wyznaczone numerycznie pola temperatur dla typowego procesu kucia na gorąco, oparte o próby plastometryczne na symulatorze Gleeble 3800, oraz kontrolowane chłodzenie po kuciu.W oparciu numeryczną analizę parametrów termo-mechanicznych i zmian temperatury odkuwki modelowej dobrano warunki procesu kształtowania oraz sch...

show abstract

Microstructure and mechanical properties of microalloyed steel forgings manufactured from cross-wedge-rolled preforms

Cited by 18 publications

References 7 publications

Mechanical properties of ausforged 27MnSiVS6 microalloyed steel

Mechanical properties of ausforged 27MnSiVS6 microalloyed steel

A simple constitutive model for predicting flow stress of medium carbon microalloyed steel during hot deformation

Design of Controlled Processing Conditions for Drop Forgings Made of Microalloy Steel Grades for Mining Industry

Contact Info

Product

Resources

About